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MOSCOW, June 5 Russian gas producer Gazprom and Ukrainian state-owned company Naftogaz will not hold gas talks on Thursday, two sources said, after this week's negotiations in Berlin seemed to bring the two sides closer.
Russia has given Ukraine until Tuesday to pay off at least part of its debt, which Gazprom puts at $4.46 billion, and agree to terms for future deliveries, especially on price, or has threatened to reduce supplies to its neighbour.
Both companies held talks for two days in Berlin earlier this week to try to settle the dispute which could potentially threaten gas flows to Europe.
Gazprom and Naftogaz declined to comment.
European Commission spokeswoman Sabine Berger said: "We are in contact with the parties involved and aim to organise a trilateral meeting soon, but so far no date and venue have been set." The Russian Energy Ministry declined to comment.
On Tuesday, Ukrainian Prime Minister Arseny Yatseniuk hinted that his cash-strapped country would be more flexible over its price demands, although he made clear the price sought by Russia remained far too high.
Ukraine wants to return to a discounted gas price of $268.5 per 1,000 cubic metres, granted by Moscow as a concession after Ukraine's then president Viktor Yanukovich dropped plans to sign agreements on closer political and trade ties with the EU.
After Yanukovich was ousted in February following months of protests provoked by his policy U-turn, Russia reinstated the earlier price of $485 - the highest in Europe.
Following talks on Wednesday, Naftogaz said it was waiting for Gazprom's proposals on revising the 2009 gas contract that locked Kiev into paying the higher price. It did not disclose details.
It said that if there was no compromise by Friday, Naftogaz would pay off remaining gas debts no sooner than June 10.
Gazprom says Ukraine owes it a total of $4.46 billion in gas debts, including $1.45 billion for November-December and another $3 billion for April-May. Naftogaz paid off $786 million last week. (Reporting by Denis Pinchuk in Moscow, Pavel Polityuk in Kiev and Barbara Lewis in Brussels; writing by Katya Golubkova, editing by Elizabeth Piper)